Jelly Beans!

So this is the first week back in the classroom in a little while. I've been working on project one's write-up and making the video/keynote/screenflow presentation. We did the jellybean lab that was part of the presentation this summer. Duke started off with a series of reaction demonstrations so the students would get excited about what was going to be taught. Their first demo was glycerine and potassium permanganate. This is an oxidizing reaction that is highly exothermic. The students really like the demo because there is a sudden reaction where it bursts into flame.

Second he walks them through a reaction of copper and silver nitrate. So the silver crystals grow and he walks them through the reaction on the board so they see everything written out. This is a single replacement reaction. Then he shows them a reaction with NaCl and AgNO3. This is a double replacement reaction that shows a color change to white from a colorless set of solutions being mixed. This is also a chance to talk to students about something being colorless vs. something being clear. Koolaid is used as an example of a clear solution that has a color. All of the students had seen Koolaid or Gatorade or something like that (a student was actually drinking some gatorade in class, so that worked out well). He also talks about solids forming in milk, which you can't see through (referring to it as chunky milk... eww...). The next demo is magnesium and hydrochloric acid. This produces hydrogen and is exothermic. Students get excited and start naming what types of reaction indicators they see. They get into diatomic molecules and pairing.

The final reaction is methanol and fire. They see a reaction with O2. The second period had a particularly violent reaction since Duke used more methanol. They got it on video and several people screamed. It was a pretty great moment of science. So then Duke talked about what students saw and what was created in the reaction.

Then we move on to the jellybean work. Students are fist given a set of jellybeans that they can eat. This is a "blueberry muffin" set of jellybeans. This gives the students a common experience with these jellybeans. If they haven't experienced them, or haven't made recipes from them, this catches them up to the other students. Either they like it or they don't, but at least they remember it. Students are then broken up into groups of two at the lab stations, they check to make sure they have the proper number of jellybeans, then start making their chemical equations. So Duke and I walked around to help the students work through their "chemical" equations and the balancing. Students generally took a few tries to really get what they were doing, but usually got what was happening in the end. We checked whether they understood what was going on by then giving them real chemical equations to balance. First and third period got it a little faster than second period, which is to be expected.